Information aimed at modifying HIV/AIDS- relevant behaviors is communicated through posters, brochures, government documents, educational videotapes, celebrity testimonials, print advertisements, and public service announcements. Yet, little attention has been focused on how to create such messages so that they are more likely to have maximum impact. This program of research investigates whether the principles of message framing derived from Prospect Theory can be used to enhance the persuasiveness of HIV/AIDS information directed toward relatively poor, inner-city women. Persuasive messages can be framed as gains and emphasize the benefits of performing an action, or as losses and emphasize the risk of not performing that action. Many of the communications developed to promote safer sex behaviors or HIV-testing are framed in loss terms, focusing on the risk of not changing one's habits. Yet, according to Prospect Theory, there are conditions under which gain-framed messages might be more persuasive. This program or research tests three hypotheses concerning the situation in which gain-framed messages are most persuasive and the situation in which loss-framed messages are most persuasive, and it examines two hypotheses concerning the mechanism accounting for framing effects. To test these hypotheses, three field experiments are proposed involving women attending a community health care center. An important goal of this line of research is to be able to articulate a set of principles concerning message framing and HIV/AIDS- relevant behaviors that can be adopted by health communication practitioners and AIDS service organizations.